Means for detecting caught threads in circular looms



Jan. 24, 1950 v M J ANCET 2,495,501

' MEANS FOR DETECTING CAUGHT THREADS IN CIRCULAR LOOMS Filed- March 18,1948 Patented Jan. 24, 1950 Victor 'Marie Joseph Ancet, Lyons, France,as-

signor to Regina S. A., Tangiers, Morocco r Application March is, 1948,,Serial No. 15,556 In France March 31, 19/97 This invention relates toloom stop motions I and is concerned more particularly with a novel.stop motion, whichoperates to stop the loom in the event that the warpshed is not properly openedfor'the passage of the shuttle. Thenew stopmotion may ,be utilized in looms of various types and is especiallyadapted for ,use'on circularlooms. An application of the stop motion toa circular 100m of the type, in which the warp threads undergoingshedding [extend verztically, will, accordingly, be illustrated anddescribedin detail fforpurpos'es of explanation.

, In the operation o'floomsfit sometimes happens that the shed .does notopen properly to permit the shuttle to pass through it and this mayresult from-a-deiectin the shedding mechanism or because of the presenceof a foreign body among-the'warp threads. "In circular looms, inparticular, the breaking of a warp thread permits the :thread to dropdown -and -the broken thread may be carried along by the shuttle, sothat it takes the position of 'a weft thread that has beenimproperly-inserted, andhindersor'prevents the opening of the shed inthe next shedding operation. When the warp threads are not properlyseparated into two sheets of a shed through which the shuttle may pass,the shuttle should be stopped promptly and before it reaches theobstruction, since otherwise damage may be done to the warp.

Heretofore, a number of expedients for stopping a loom upon theoccurrence of an insufliciently opened shed have been proposed, but suchdevices have acted in response to contact of the shuttle with the warpthreads not properly separated in the formation of the shed. As aresult, the proposed stop motions have necessarily functioned toeffectso rapid a stoppage of the loom as to put a strain upon it and, inorder that they may be effective, it has been necessary to limit thespeed of the shuttle.

The present invention is, accordingly, directed to the provision of anovel stop motion for looms, which functions to stop the loom upon theoccurrence of an improperly formed shed and before the shuttle has comeinto contact with the obstruction in the shed. When the new stop motionis employed on a circular loom, in which shedding is a gradualoperation, a considerable interval of time is available after thefunctioning of the mechanism'before the shuttle can reach theobstructedpartof the shed, sothat the shuttle may be driven at a highspeed.

For a'better understanding of the invention, reference may be made 'to.the accompanying drawing, in which Fig. 1 is a diagrammatic perspectiveview of portions of a circular loom equipped with the new stop motion;and

Figs. 2 and 3 are fragmentary plan views of the stop motion, showing itsmode of operation.

The circular loo'm diagrammatically illustrated in Fig; 1 includes anaxial main shaft 10, which operates through mechanical orelectromagnetic means '(not shown) for propelling one or more shuttlesllthrough a .circularpath above a reed 1'2. The .warp threads 13 aremanipulated by 'harness'mechanism "(notshowm to form a shed, throughwhich each shuttle moves,'the shed opening ahead ofth'e shuttle andclosing behind it, asit travels along.

' An arm f4 for each shuttle is mounted on shaft +0 to extend toward thewarp threads and the arm rotates with the shaft and lies ahead of itsshuttle in the direction of travel of the latter. At its outer end, eacharm carries a plate 15 of insulating material and a metal detectingfinger I5 is mounted for swinging movement on a metal pin l1 extendingthrough the plate. Thefinger is connected through a spring l8 to a posti9 mounted on the plate and is urged by the spring to swing toward afixed terminal 20 carried by the plate. The pin I1 is connected in acircuit with a solenoid 2| and a battery 22, one side of which isgrounded, and terminal 2! is grounded through a connection 23. The plateI5 is slotted and held adjustably on arm l4 by a screw 24 passingthrough the slot and into the arm.

Solenoid 2| operates, when energized, to open switch 25 in a circuitwith control means 26 controlling the supply of current to motor 21driving the loom. When switch 25 is opened, the control means cuts offthe current to the motor and the loom stops.

In the use of the new stop motion, plate I5 is initially adjusted on thearm It, so that the s end of finger l6, which extends beyond the edge ofthe plate, projects into the inner sheet of warp threads in the fullyopened shed, that is. into the sheet lying closer to the loom axis. As

shaft It rotates carrying arm M with it, finger 16 engages the warpthreads l3 in the inner sheet successively and, as the finger snaps byone warp thread, it engages and is held back by the next, so that itcannot engage the terminal 23. If a warp thread, such as that designatedIsa, breaks and drops down, it is likely to be carried along by oneshuttle, so that, when the shed is to be opened for the followingshuttle, thread I30, will prevent the shed from opening. When thatoccurs, the finger I6 of the stop motion preceding the second shuttlewill reach a point adjacent the obstructed thread, where there is nowarp thread in its path. The finger will, thereupon, be swung by itsspring 18 against contact 26. This will complete the circuit throughsolenoid 2| and switch 25 will be opened to cut off the supply ofcurrent to the motor 21, so that the loom will stop.

It will be apparent that, with the construction described, the stopmotion, which prevents engagement of a shuttle with an obstruction inthe shed, lies a substantial distance angularlyahead of the shuttle. Theinterval between actuation of the stop motion and stopping of the loom,may, therefore, be much longer than would be permissible, if the stopmotion were carried by the shuttle assembly, so that the loom may bestopped with less strain. Also, for the same reason, a higher shuttlespeed is possible.

What I claim is:

1. In a loom having driving means, means actuated by the driving meansfor forming the warp threads into a shed, a shuttle moved through theshed by the driving means, and means controlled by an electric circuitfor stoppingthe loom, the combination of a mounting advanced by thedriving means along the path of the shuttle and ahead of the shuttle, acontact forming part of the circuit and carried by the mounting, adetectorfinger movably mounted on the mounting and normally engagingsuccessive warp threads forming one sheet of the shed,

the finger being in the circuit, and a spring acting on the finger andurging it toward the contact to close the circuit, the finger being heldby its engagement with the warp threads in said 4 sheet from being movedinto engagement with the contact.

2. In a loom having driving means, means actuated by the driving meansfor forming the warp threads into a shed, a shuttle moved through theshed by the driving means, and means controlled by an electric circuitfor stopping the loom, the combination of a mounting advanced by thedriving means along the path of the shuttle and ahead of the shuttle, acontact forming part of the circuit and carried by the mounting, adetector finger pivotally mounted on the mounting with one end normallyengaging successive warp threads forming one sheet of the shed, thefinger being in the circuit, and a spring acting on the finger andurging it to swing to engage the contact and close the circuit, thefinger being held against such swinging movement by its engagement withthe warp threads in said sheet.

3. In a loom having driving means, means ac- I warp threads into a shed,a shuttle moved through the shed by the driving means, and meanscontrolled by an electric circuit for stopping the loom, the combinationof an arm rotated on the axis of the loom by the driving means and lyingahead of the shuttle, a contact mounted on and insulated from the arm,the contact being in the circuit, a detector finger movably mounted onand insulated from the arm, the finger being in the circuit and normallyengaging successive warp threads in one sheet of the shed, as the armrotates, and a spring urging the finger toward the contact to close thecircuit, the finger being held by its engagement with the threads insaid sheet from being moved to engage the contact.

VICTOR MARIE JOSEPH ANCET.

REFERENCES CITED UNITED STATES PATENTS- Name Date Jabouley July 9, 1935Number

